The North American Numbering Plan (NANP), which is the present day area code system, was designed by AT&T and Bell Laboratories in the 1940's in order to make it possible to route long distance phone calls automatically. A telephone number implemented in accordance with the NANP includes ten digits, the first three digits of which form the area code and identify the geographic area in which the called party lives, the second three digits of which identify the central office or switch within the area code, and the last four digits of which identify the individual telephone line numbers. Although there are theoretically 1000 blocks of phone numbers (ten thousand phone numbers for each block) available for each code, currently, only 792 blocks of phone numbers are actually available, assuming that some phone numbers, such as 0, 1, and 911 cannot be used. State utilities regulators allocate these blocks of phone numbers among individual phone companies on an as-needed basis, without regard to whether all of the phone numbers within the previously allocated blocks have been assigned to their customers. Once the respective state utilities regulator has allocated all of the phone number blocks in a particular area code, a new area code must be added to supplement the coverage of the old area code by implementing an area code split or an area code overlay system. There are 680 usable area codes available for assignment, with over 255 area codes being in service within the United States and other countries, such as Canada and a number of Caribbean nations.
With regard to the area code split system, a region having one area code is split into two regions having separate area codes, with one region retaining the old area code and a second region acquiring a new area code. For example, a large region that previously was assigned “679” as the area code could be split into two smaller regions with respective area codes “679” and “313,” as was demonstrated in the greater Los Angeles region in the 1980's. The benefit of the geographical split system over the overlay system is that a particular geographical region is defined by a single area code. The disadvantage, however, is that such geographical area code splitting is frustrating, inconvenient, and costly to consumers and industry. When area codes change, consumers have to notify acquaintances of the change and reprogram telecommunications equipment and home-alarm equipment, while businesses must reprint stationery, update customer-contact databases, and risk losing old customers who do not have their new area code. This inconvenience is heightened when users living in the same area code, prior to the area code split, must now dial an extra four digits (“1” and the three-digit area code) when calling between the split regions.
Less common, but being used more frequently, the area code overlay system involves overlaying the new area code over the old area code, i.e., all new phone lines that are incorporated into a region having a specific area code are given a new code. This is seen as being less disruptive than geographically splitting a region into two area codes, since no current phone number is subjected to an area code change. The overlay system, however, does have certain disadvantages. For example, a particular geographical region may be defined by more than one area code, in which case, a particular household or business having an existing phone line may reside in two different area codes if another phone line is installed subsequent to the overlay implementation. Significantly, all users within an area code overlaying region must dial a long distance phone number, i.e., an additional four digits, even if they reside in the same area code region. Currently, the state of Maryland, and certain cities in Texas, Georgia, Florida, and Colorado, have implemented area code overlay systems. Cities in California and Pennsylvania plan to implement such systems in the near future.
In the last two decades, the number of area code additions has dramatically increased due to the proliferation of fax machines, online services, cellular phones, pagers, automatic teller machines, credit card approval systems, etc., as well as the increased number of local phone numbers to which blocks of phone numbers must be assigned. By way of example, the United States had one hundred nineteen area codes in service in 1991, which has almost doubled to two hundred fifteen today. It is projected that, between 1992 and 2002, the number of area codes in California, alone, will increase from thirteen to forty-one.
As a result of the increase in area code additions, there has been an increased pressure on state utilities regulators to implement area code conservation plans to slow the proliferation of such area code splits and overlays. Such plans may involve efficiently allocating phone numbers, e.g., by reducing the number of phone numbers allocated to a particular phone company at one time from ten thousand to one thousand. Also, these plans may involve conserving phone numbers by requiring phone companies to give back unused phone numbers for redistribution. Ultimately, the extended life of any given area code depends on when the phone conservation process is initiated, how many numbers are allocated, how many numbers are reclaimed, and the demand of numbers. Area code conservation plans are largely untested, however, and any success that may result from the implementation of any of these plans is questionable. Regardless of the extent to which the life of an area code is positively impacted by the implementation of an area code conservation plan, these measures are seen as a temporary fix since the demand for phone numbers will eventually exceed the phone number supply, thereby necessitating the addition of area codes.
There thus remains a need for apparatus and methods that minimize any annoyance that may be presented to users residing in geographic regions where split or overlay area code systems have been implemented.